Russ, i can't get enough of those pictures.:)
The timing worked out where I am still in Va taking care of my daughter until early July, so they are getting all the fun. He said that he did feel it was too rich, especially the accel pumps (no surprise) so they may mill the pump cams down a bit. It does apparantly balk just a bit when dumping the throttle before it jumps, but I am not there so cannot really tell you why. I fully expected this for a number of possible reasons, so I just have to tune transition. He also said it respoded cleanly to the idle set screws, so that it good (new carbs really are so much better than an unknown). It's currently got 52 idles and 145 mains, and I am thinking I may get away with 50 idles and 150 mains and a sl leaner A/C (200?). With this first dyno, just hoping to rough out the mixtures and ignition advance to get it safe. Here's hoping!
Don't all of us Weber pilots have this problem? I know that I do... Almost lost me a traffic light sprint the other day. Cost me a good 30 feet before I could (quickly) catch up with that 3.0 BMW Z4... How does the location of the lambda sensor work out for you Russ? I received the weld-on ring in the mail yesterday. I'm now on the fence: should I weld it in the header, upstream of the ball joint (at considerable effort to take the header out, for which one needs to undo the engine mounts and lift the engine a bit), or could I simply take the muffler off and weld it on one of the intake pipes to that one? Risk of the latter option: if there's air ingress through the ball joint gasket, the O2 measurements are bogus... Hans
While locating the sensor in the header collector would be optimal, even Ferrari placed it after the header flange and before the cat in the lambda cars. I also opted on placing it on the proximal muffler tube, and have all new hardware and expansion gaskets, with very good results. I think while the air leak risk is real, it is not at all likely if the usual precautions are taken. I would think the muffler intake pipe will work well - I am also counting on it. While not wanting to turn this into a Weberology discussion, balking at dumping the throttle can primarily be due to four things: 1. ignition 2. too much accel pump 3. too little accel pump 4. not enough flow velocity. Each one is tuneable, just have to see what it is. And before someone points it out, yes, 2,3 &4 are a bit inter-related. Once I get ithe LM-1 on the car and out driving, I'll post some graphs on the tuning changes. I have a gut hunch that the 38mm venturi may be just ever so slightly too big for the lower running and transition, but a good match for high end once good flow is achieved above 4000 rpm. The book says 38mm should be fine, so I'll be into the Weber tuning box to make it work...
I am still trying to figure out when you found the time to do THIS AND rebuild the engine and cockpit in your T-28?
Russ, Let me add one more interrelated variable to your list, pump shot duration, a function of at least the pump cam, output nozzle and maybe the diaphram spring too. Like most things, what works best when dumping the throttle may not be optimum when exiting a turn. There are always compromises. Best, Bill
Thanks everyone. First dyno is scheduled tomorrow for 10:30 - and of course it will be one of the hottest days of the year in the least favorable circumstances. Many thanks to James and everyone at Norwoods. Image Unavailable, Please Login
Hey Russ, What's all the fuss about? When I look at that last photo, I see a bone stock engine compartment!!! Hats off to you for making it look to "belong" in there. Looking forward to seeing the dyno results... Hans
Ok, i got back from breakfast and had time to go to the market too. Where are the #'s?? Where's Russ?? Hello??
